What to monitor?

Docker manager - a API endpoint for monitoring the status is available at /api/status, consult the api docs for more info.

Docker worker container - check that the worker container is running on all worker nodes.

(Optional) routing layers - changes depending on your design.

App containers - check that the app containers are running on your worker nodes - adding a HEALTHCHECK configuration to the Dockerfile will make Nebula automatically restart containers marked as "unhealthy" and is therefor highly recommended.